Soldering or brazing of pipe or tubing requires that the mating (or faying) surfaces of the pipe and fittings be thoroughly cleaned to present oxide-free and contaminant free surfaces which can be wetted by the molten solder or brazing alloy. This is required to form sound joints which are free of porosity and voids and which do not leak.
This is normally accomplished by degreasing the joint components, if necessary, and then abrading the faying surfaces. Degreasing is accomplished by wiping with a solvent appropriate for the oily contaminant to be removed. Oxides and dry contaminants are manually removed by rubbing with dry steel wool, emery cloth, or wire brushes. They may also be removed by using motor driven brushes or emery cloth.
Proper cleaning of joint members prior to soldering or brazing is essential in order to economically form sound joints. Clean joint surfaces can be rapidly soldered or brazed using a minimum of heat, flux, and filler alloy. These economies of time, energy, and materials more than offset the cost of proper cleaning.
Manual cleaning of a large number of tube/fitting joint components can become tedious and time consuming and can, thus, lead to operator inattention and error. Clearly, motor driven abrasion means can eliminate tedium and permit rapid and effective cleaning of large numbers of joint components.
One such motor driven device has been disclosed in U.S. Pat. No. 3,188,674 by R. L. Hobbs in June 1965. This consists of a drill mounted brush holder for cleaning the outer surface of tube ends prior to soldering or brazing. It also includes provision for adjustment of the replaceable brush to account for wear. It provides the advantages of being motor driven, having replaceable brushes, and having adjustment capability for the brush.
This device cannot be used for cleaning the inside surfaces of fittings, and it may only clean part of the tube edge. Its design requires a different unit for each size of tube to be cleaned. This is not a disadvantage in a manufacturing plant where a great number of assemblies are made using a single tube diameter. It may, however, be inconvenient to a household plumber who may have to install several different sizes of tubing and fittings.
It is an object of this invention to provide a means for cleaning the ends of pipe or tubing and fittings prior to soldering or brazing. It is a further object to provide said means in such a manner as to permit cleaning of two or more sizes of tubing and fittings using a single tool. It is a still further object to provide said cleaning means with a device which is operable by manual or motor driven means.